Zergs are part of wvw, there is no way around it, its here to stay, however what if there were a way to encourage or force smaller fights? This might be achieved by;
10v10v10 Dungeon in a wvw zone, where only the high ranked player can enter this persistent zone, filled with elites, traps and rewards. you fight your way to the bottom, and claim a relic that bolsters your whole wvw side with stat bonuses. taking the relic applys a 30 min lockout, after which it has to be defended from opposing realms and epic mobs.
dungeon towers, for all ranks, these towers appeared from no where at random over the wvw maps, you can enter these solo or in groups for 10v10v10, taking a tower gives minor boosts to stats.
please post some of your ideas